ios - 为什么导航栏按钮项目在 textview 已被 resignedFirstResponder() 时不起作用？

Question

这是一个奇怪的问题。我有两个条形按钮项，一个是取消，一个是完成。完成按钮将文本保存在 coreData 中的 TextView 中，然后从导航 Controller 中弹出当前 View 并转到上一个 View Controller 。取消按钮只是转到前一个 Controller 。当 textview 是 firstResponder() 或键盘启动时，整个过程都有效。当键盘退出作为 firstResponder 时，两个按钮都不起作用。就像什么都不做一样。完成按钮不保存文本，也不带我到以前的 View Controller 。

这是两个按钮的代码:

完成按钮:

 @objc func handleDoneButton() {
    print("hello")
    if edittaskview.text.isEmpty == true
    {
        moContext.delete(editnotes!)
    }
    else
    {
        editnotes?.sNote = edittaskview.text
    }
    var error: NSError?
    do {
        // Save The object

        try moContext.save()
        print("SAVED")
    } catch let error1 as NSError {
        error = error1
    }

    _ = navigationController?.popViewController(animated: true)


}

取消按钮:

 @objc func handleCancelButton()
{
    _ = navigationController?.popViewController(animated: true)
}

同样，只有当 textview 是第一响应者时，当按钮被点击时，这两个函数中的代码才起作用，否则它们不会。

View Controller 代码:

import UIKit
import CoreData

 class editViewController: UIViewController, UICollectionViewDelegate, 
  UICollectionViewDataSource, UICollectionViewDelegateFlowLayout, 
UITextViewDelegate, UIGestureRecognizerDelegate{
 var editnotes: addednotes?
var prioritynumber: Int = 1
let moContext = (UIApplication.shared.delegate as! 
AppDelegate).persistentContainer.viewContext
var colorArray = [prioritylevels]()
lazy var edittaskview: UITextView = {
    let textview = UITextView()
    textview.isScrollEnabled = false
    textview.font = UIFont.systemFont(ofSize: 16)
    textview.backgroundColor = .white
    textview.delegate = self

    return textview
}()
var clearview: UIView = {
   let view = UIView()
    view.backgroundColor = .clear
    //view.isUserInteractionEnabled = false
    return view
}()
let rightBarButton = UIBarButtonItem(title: "Done", style: .done, target: self, action: #selector(handleDoneButton))
let leftBarButton = UIBarButtonItem(title: "Cancel", style: .done, target: self, action: #selector(handleCancelButton))

lazy var priorityCV: UICollectionView = {
    let layout = UICollectionViewFlowLayout()
    layout.minimumInteritemSpacing = 0
    let cv = UICollectionView(frame: .zero, collectionViewLayout: layout)
    cv.delegate = self
    cv.dataSource = self

    return cv
}()

let line: UIView = {
    let line = UIView()
    return line
}()

let reminderView: UIView = {
   let reminder = UIView()
    reminder.backgroundColor = .white
    return reminder
}()

let reminderTitle: UILabel = {
   let title = UILabel()
    title.text = "Due Date"
    title.textColor = .black
    title.font = UIFont(name: "Avenir Next", size: 16)
    title.font = UIFont.boldSystemFont(ofSize: 16)

    return title
}()
let reminderMsg: UILabel = {
    let title = UILabel()
    title.text = "No Due Date Set"
    title.textColor = .black
  //  title.font = UIFont(name: "Avenir Next", size: 12)
    title.font = UIFont.systemFont(ofSize: 12)

    return title
}()
let reminderAddBtn: UIButton = {
    let btn = UIButton(type: .system)
    btn.setTitle("Set", for: .normal)
    btn.setTitleColor(.black, for: .normal)
    btn.titleLabel?.font = UIFont.systemFont(ofSize: 14)
    btn.addTarget(self, action: #selector(handleSetReminderBtn), for: .touchUpInside)
    return btn
}()

var textHeightConstraint: NSLayoutConstraint?

override func viewWillAppear(_ animated: Bool) {
    adjustTextViewHeight()
}
 let datePicker: UIDatePicker = UIDatePicker()

override func viewDidLoad() {
    super.viewDidLoad()
    view.backgroundColor = UIColor(red:0.97, green:0.97, blue:0.97, alpha:1.0)

    datePicker.addTarget(self, action: #selector(datePickerValueChanged(_:)), for: .valueChanged)
    //ColorArray for PriorityCV
    colorArray = [prioritylevels(color: UIColor(red:0.00, green:0.78, blue:0.73, alpha:1.0), name: "   Low", prioritynumber: 1), prioritylevels(color: UIColor(red:0.00, green:0.78, blue:0.35, alpha:1.0), name: "Medium", prioritynumber: 2),prioritylevels(color: UIColor(red:0.88, green:0.63, blue:0.00, alpha:1.0), name: "  High", prioritynumber: 3), prioritylevels(color: UIColor(red:0.96, green:0.28, blue:0.70, alpha:1.0), name: "Urgent", prioritynumber: 4)]



    priorityCV.register(UICollectionViewCell.self, forCellWithReuseIdentifier: "cvid")

    navigationItem.title = "Edit Task"
    self.navigationItem.setHidesBackButton(true, animated: false)
    self.navigationController?.navigationBar.tintColor = UIColor.white
    navigationItem.rightBarButtonItem = rightBarButton
    navigationItem.leftBarButtonItem = leftBarButton
    view.addSubview(clearview)
    clearview.addSubview(line)
    clearview.addSubview(edittaskview)
    clearview.addSubview(priorityCV)
    clearview.addSubview(reminderView)
    reminderView.addSubview(reminderTitle)
    reminderView.addSubview(reminderMsg)
    reminderView.addSubview(reminderAddBtn)
    edittaskview.text = editnotes?.sNote
    edittaskview.becomeFirstResponder() //taskview becomes first responder here when the view is loaded. 
//        view.addSubview(datePicker)


    setupViews()
    line.backgroundColor = editnotes?.sPriorityColor

    let dismissbytap =  UITapGestureRecognizer()
    dismissbytap.addTarget(self, action: #selector(handleDismissByTap))
    dismissbytap.delegate = self
    clearview.addGestureRecognizer(dismissbytap) //a clear uiview is added behind all the subviews.  this uiview is used to dismiss keyboard when tapped on it.

}

override func didReceiveMemoryWarning() {
    super.didReceiveMemoryWarning()
    // Dispose of any resources that can be recreated.
}


func collectionView(_ collectionView: UICollectionView, numberOfItemsInSection section: Int) -> Int {
    return colorArray.count
}

func collectionView(_ collectionView: UICollectionView, cellForItemAt indexPath: IndexPath) -> UICollectionViewCell {
    let cell =  collectionView.dequeueReusableCell(withReuseIdentifier: "cvid", for: indexPath)
    cell.backgroundColor = colorArray[indexPath.row].color
    let prioritylabel = UILabel(frame: CGRect(x: view.frame.width / 20, y: 0, width: view.frame.width / 4, height: 30))

    cell.addSubview(prioritylabel)
    prioritylabel.text = colorArray[indexPath.row].name
    prioritylabel.textColor = .white
    return cell
}

func collectionView(_ collectionView: UICollectionView, layout collectionViewLayout: UICollectionViewLayout, sizeForItemAt indexPath: IndexPath) -> CGSize {
    return CGSize(width: view.frame.width / 4, height: 30)
}
func collectionView(_ collectionView: UICollectionView, didSelectItemAt indexPath: IndexPath) {

    prioritynumber = colorArray[indexPath.row].prioritynumber
    line.backgroundColor = colorArray[indexPath.row].color
    editnotes?.sPriorityColor = colorArray[indexPath.row].color
    editnotes?.sPriorityNumber = prioritynumber
    print(prioritynumber)
}
func setupViews()
{
   _ = edittaskview.anchor(line.bottomAnchor, left: view.leftAnchor, bottom: nil, right: view.rightAnchor, topConstant: 2, leftConstant: 0, bottomConstant: 0, rightConstant: 0, widthConstant: 0, heightConstant: 0)
    self.edittaskview.contentInset = UIEdgeInsetsMake(2, 8, 4, 8)

    self.textHeightConstraint = edittaskview.heightAnchor.constraint(equalToConstant: 80)
    self.textHeightConstraint?.isActive = true
    self.adjustTextViewHeight()
    _ = clearview.anchor(view.topAnchor, left: view.leftAnchor, bottom: view.bottomAnchor, right: view.rightAnchor, topConstant: 0, leftConstant: 0, bottomConstant: 0, rightConstant: 0, widthConstant: 0, heightConstant: 0)
  _ = priorityCV.anchor(edittaskview.bottomAnchor, left: clearview.leftAnchor, bottom: nil, right: clearview.rightAnchor, topConstant: 0, leftConstant: 0, bottomConstant: 0, rightConstant: 0, widthConstant: 0, heightConstant: 30)
  _ = line.anchor(clearview.topAnchor, left: clearview.leftAnchor, bottom: nil, right: clearview.rightAnchor, topConstant: 0, leftConstant: 0, bottomConstant: 0, rightConstant: 0, widthConstant: 0, heightConstant: 4)

  _ = reminderView.anchor(priorityCV.bottomAnchor, left: clearview.leftAnchor, bottom: nil, right: view.rightAnchor, topConstant: 30, leftConstant: 0, bottomConstant: 0, rightConstant: 0, widthConstant: 0, heightConstant: 60)
    _ = reminderTitle.anchor(reminderView.topAnchor, left: reminderView.leftAnchor, bottom: nil, right: nil, topConstant: 8, leftConstant: 8, bottomConstant: 0, rightConstant: 0, widthConstant: 100, heightConstant: 20)
    _ = reminderMsg.anchor(reminderTitle.bottomAnchor, left: reminderView.leftAnchor, bottom: nil, right: nil, topConstant: 4, leftConstant: 8, bottomConstant: 0, rightConstant: 0, widthConstant: 100, heightConstant: 24)
    _ = reminderAddBtn.anchor(reminderView.topAnchor, left: nil, bottom: nil, right: reminderView.rightAnchor, topConstant: 20, leftConstant: 0, bottomConstant: 20, rightConstant: 32, widthConstant: 30, heightConstant: 20)
}

@objc func handleDoneButton() {
    print("hello")

    if edittaskview.text.isEmpty == true
    {
        moContext.delete(editnotes!)
    }
    else
    {
        editnotes?.sNote = edittaskview.text
    }
    var error: NSError?
    do {
        // Save The object

        try moContext.save()
        print("SAVED")
    } catch let error1 as NSError {
        error = error1
    }

    _ = navigationController?.popViewController(animated: true)


}

func textViewDidChange(_ textView: UITextView) {
    self.adjustTextViewHeight()
}


func adjustTextViewHeight() {
    let fixedWidth = edittaskview.frame.size.width

    let newSize = edittaskview.sizeThatFits(CGSize(width: fixedWidth, height: CGFloat.greatestFiniteMagnitude))
    self.textHeightConstraint?.constant = newSize.height + 15

    self.view.layoutIfNeeded()
}


@objc func handleCancelButton()
{
    _ = navigationController?.popViewController(animated: true)
}


@objc func datePickerValueChanged(_ sender: UIDatePicker) {
    let componenets = Calendar.current.dateComponents([.year, .month, .day, .hour, .minute], from: sender.date)
    if let day = componenets.day, let month = componenets.month, let year = componenets.year, let hour = componenets.hour, let minute = componenets.minute  {
        print("\(day) \(month) \(year) \(hour) \(minute)")
    }
}

@objc func handleDismissByTap() {
    edittaskview.resignFirstResponder() // Resigning textview as first responder


}

func gestureRecognizer(_ gestureRecognizer: UIGestureRecognizer, shouldReceive touch: UITouch) -> Bool {
   return touch.view == gestureRecognizer.view
}

Answer 1

这看起来确实很奇怪 - 我不知道为什么导航栏按钮只在您的 TextView 处于事件状态时调用函数，但是...

解决它的一种方法是将左右 UIBarButtonItem 声明移动到 viewDidLoad() 而不是在类级别。

顺便说一句，如果将 edittaskview.becomeFirstResponder() 从 viewDidLoad() 移动到 viewDidAppear()，您将获得更好的动画和键盘外观。